*The study of nutrients and how the body utilizes them.

o required in large amounts o provide potential energy expressed in calories  the amount of heat required to raise the temperature of a gram of water 1degree Celsius  calorie used to measure food energy is 1,000 greater (Cal-kilocalorie)  1g of carbs=4 calories  1g of protein=4 calories  1g of fat=9 calories o include carbohydrates, lipids, and proteins

organic compounds that include sugars and starches energy in chemical bonds power cellular processes forms glycogen which is stored in liver and muscles; if not utilized this is converted into fat forms ribose and deoxyribose produce lactose intake of at least 125 to 175g daily Starch: grains & vegetables Glycogen: meats Disaccharides: sugar & molasses Monosaccharide: honey & fruit Cellulose: complex carb we cannot digest (celery, corn)

Organic compounds that include fats, oils, cholesterol, phospholipids, and triglycerides Supply energy for cellular processes Building structures (cell membranes) Saturated fats- animal origin (meat, eggs, milk) Unsaturated fats: plant origin (seeds, nuts, plant oils) Intake not exceed 30% of calories *low-fat labels usually means more sugar=more calories

Polymers of amino acids: needed for cell growth and repair Control metabolic rates Clotting factors Keratin of skin and hair Water balance Hormones Energy Include meat, fish, poultry, cheese, nuts, milk, eggs

o Required in smaller amounts o Include minerals and vitamins o Make possible the biochemical reactions that extract energy from macronutrients

 Vitamins required in small amounts for normal metabolic processes body does not make enough so we must take them in Fat-soluble: dissolve in fats; accumulate in tissue; can overdose (see table) Vitamin A, D, E, K Water-soluble: dissolve in water (see table) Vitamin B, C

 Minerals Inorganic elements that are essential in human metabolism 4% of body weight Most concentrated in bones and teeth Nerve impulse conduction Muscle fiber contraction Blood coagulation Maintain body pH Major minerals: Ca & P account for 75% of minerals (see table) Trace elements: essential minerals in small amount (see table) *the human body has enough P to make 2 thousand match sticks *enough iron to make a small nail

 Essential nutrients o Nutrients that human cells cannot synthesize o Include amino acids